fixed wrong height and latitude

1manprojects · Dec 2, 2018 · 889cf88 · 889cf88
1 parent 539e427
commit 889cf88
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Showing 6 changed files with 47 additions and 14 deletions.
diff --git a/.vs/One_Sgp4/v15/.suo b/.vs/One_Sgp4/v15/.suo
diff --git a/.vs/One_Sgp4/v15/Server/sqlite3/storage.ide b/.vs/One_Sgp4/v15/Server/sqlite3/storage.ide
diff --git a/.vs/One_Sgp4/v15/Server/sqlite3/storage.ide-wal b/.vs/One_Sgp4/v15/Server/sqlite3/storage.ide-wal
diff --git a/OneSGP4_Example/Program.cs b/OneSGP4_Example/Program.cs
@@ -62,6 +62,20 @@ static void Main(string[] args)
             //Get Local SiderealTime for Observer
             double localSiderealTime = startTime.getLocalSiderealTime(observer.getLongitude());
 
+            //TESTING MIR
+
+            //TEST ECI
+            EpochTime T_eciTime= new EpochTime(09, 00, 00, 1995, 10, 1);
+            //Test GMST 
+            if (T_eciTime.getLocalSiderealTime() == 2.524218)
+            {
+
+            }
+            Coordinate T_eciCoo = new Coordinate(40, -75);
+            var t_eci = T_eciCoo.toECI(T_eciTime.getLocalSiderealTime());
+            //Coordinate equals x' = 1703.295 km, y' = 4586.650 km, z' = 4077.984 km.
+
+
             EpochTime t_time = new EpochTime(12, 46, 0, 1995, 11, 18);
             Coordinate t_cord = new Coordinate(45.0, -93);
             Sgp4Data mirPos = new Sgp4Data();
@@ -72,6 +86,27 @@ static void Main(string[] args)
             var onGround = SatFunctions.calcSatSubPoint(t_time, mirPos, Sgp4.wgsConstant.WGS_72);
             var r = t_cord.toECI(t_time.getLocalSiderealTime());
 
+
+            //TESTING
+
+
+            //Calculate SubPoint of Satellite on ground
+            while (true)
+            {
+                One_Sgp4.EpochTime time = new EpochTime(DateTime.UtcNow);
+                var test = time.getEpoch();
+                Console.Out.WriteLine(test);
+
+                var satpos = One_Sgp4.SatFunctions.getSatPositionAtTime(tleISS, time, Sgp4.wgsConstant.WGS_72);
+
+                Coordinate newC = new Coordinate(48.853333, 2.348611);
+                var look = SatFunctions.calcSphericalCoordinate(newC, time, satpos);
+                One_Sgp4.Coordinate satOnGround = One_Sgp4.SatFunctions.calcSatSubPoint(time, satpos, Sgp4.wgsConstant.WGS_72);
+                Console.Out.WriteLine(satOnGround.toString()  + " - Azimuth: " + look.y + " Elevation: " + look.z );
+                Thread.Sleep(1000);
+            }
+
+
             //Calculate if Satellite is Visible for a certain Observer on ground at certain timePoint
             bool satelliteIsVisible = One_Sgp4.SatFunctions.isSatVisible(observer, 0.0, startTime, resultDataList[0]);
 

diff --git a/One_Sgp4/One_Sgp4.csproj b/One_Sgp4/One_Sgp4.csproj
@@ -19,7 +19,7 @@
 
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;net40;net45</TargetFrameworks>
-    <Version>1.0.4</Version>
+    <Version>1.0.5</Version>
     <PackageReleaseNotes>Included Net 4.0 and Net 4.5 as TargetFrameworks</PackageReleaseNotes>
   </PropertyGroup>
 

diff --git a/One_Sgp4/SatFunctions.cs b/One_Sgp4/SatFunctions.cs
@@ -217,36 +217,34 @@ public static Coordinate calcSatSubPoint(EpochTime time, Sgp4Data satPosData,
             double sat_X = satPosData.getX();
             double sat_Y = satPosData.getY();
             double sat_Z = satPosData.getZ();
-
 
             double f = WGS_72.f;
             double wgs_R = WGS_72.radiusEarthKM;
             if (wgs == Sgp4.wgsConstant.WGS_84) {
                 f = WGS_84.f;
                 wgs_R = WGS_84.radiusEarthKM;
-            }
-
-
+            }            
             double delta = 1.0e-07;
             double f_2 = f * f;
-            double e = 2 * f - f_2;
-
+            double e = 2 * f - f_2;            
 
             double r = Math.Sqrt( (sat_X * sat_X) + (sat_Y * sat_Y) );
             double latitude = AcTan(sat_Z , r);
             double c = 1.0;
             double height = 0.0;
-            double R = wgs_R * c * Math.Cos(latitude);
 
-            for (int i = 0; i< 20; i++)
+            double phi;
+
+            do
             {
-                //R = wgs_R * c * Math.Cos(latitude);
-                c = 1.0 / (Math. Sqrt(1.0 - e * (Math.Sin(latitude) * Math.Sin(latitude))));
-                latitude = AcTan(sat_Z + (wgs_R * c * e * Math.Sin(latitude)), R);                
+                phi = latitude;
+                c = 1.0 / (Math.Sqrt(1.0 - e * (Math.Sin(latitude) * Math.Sin(latitude))));
+                latitude = AcTan(sat_Z + (wgs_R * c * e * Math.Sin(latitude)), r);
             }
+            while (Math.Abs(latitude - phi) > delta);
+
             double longitude = AcTan(sat_Y, sat_X) - time.getLocalSiderealTime();
-            height = (R / Math.Cos(latitude)) - (wgs_R * c);
-            //height = Math.Sqrt(sat_X * sat_X + sat_Y * sat_Y + sat_Z * sat_Z) - wgs_R*c;
+            height = (r / Math.Cos(latitude)) - (wgs_R * c);
 
             if (longitude < pi)
             {